Anti-implosion device for milk tanks and the like



April 26, 1966 B. E. TRAUT ETAL 3,247,859

ANTI-IMPLOSION DEVICE FOR MILK TANKS AND THE LIKE Filed March 4, 1963 2Sheets-Sheet 1 INVENTORS BERN/4R0 E. TRAUT Fm 1 F. WRZECHA AT ToFe/vE Y5April 26, 1966 B. E. TRAUT ETAL 3,247,859

ANTI-IMPLOSION DEVICE FOR MILK TANKS AND THE LIKE Filed March 4, 1965 2Sheets-Sheet 2 INVENTORS BERNARD E. TRAUT' FRANK F. WRZECHA AT TOR/VEYSUnited States Patent 3,247,859 ANTI-IMPLOSION DEVICE FOR MILK TANKS ANDTHE LIKE Bernard E. Traut and Frank F. Warzecha, Holdingford, Minn,assignors to Polar Manufacturing Company, Holdingford, Minn., acorporation of Minnesota Filed Mar. 4, 1963, Ser. No. 262,557 4 Claims.(CL 137-70) For sanitation purposes, a great majority of themilkcollection tanks presently in use are formed from the relativelynon-corrosive stainless steel. Furthermore, for

the purpose of reducing the overall height of such ve-.

.hicle-mounted tanks, most thereof are elliptical in crosssection withthe minor transverse axis thereof lying in a generally vertical plane.Such tanks obviously do not have the ability to withstand collapsingpressures that do cylindrical tanks or tanks formed from the morecorrosive steels having higher carbon content. Consequently, underadverse conditions such as brought about by frost, when the breathervalves are rendered inoperative, it is not uncommon for a relativevacuum to build up in the tank so rapidly as to cause a collapse orimplosion of the walls thereof during rapid drainage thereof by thepower pumps.

The primary object of our invention is the provision of novelanti-implosion means for tanks of the type immediately above describedwhich will automatically and positively permit entrance of air into theupper portion of a tank upon initial (but non-damaging) flexingmovements of the upper and/or lower walls thereof due to increasingvacuum built up therewithin by the conditions immediately abovedescribed.

A further object of our invention is the provision of a device of theclass described which is completely foolproof and positive in itsoperation.

A further object of our invention is the provision of a device of theclass above described which incorporates a minimum of working parts andwhich may be installed and maintained at a minimum cost.

A further object of our invention is the provision of a device of theclass above described which may be readily rinsed and is completelysanitary.

A further object of our invention is the provision of a device which maybe again rendered operative, after having functioned to preventimplosion, with a minimum of skill and a minimum of time and expense.

The above and still further objects of our invention will becomeapparent from the following specification, appended claims and attacheddrawings.

Referring to the drawings wherein like characters indicate like partsthroughout the several views:

FIG. 1 is a view in side elevation of a vehicle-mounted milk collectiontank constructed in accordance with our invention, some parts beingbroken away and some parts shown in section;

FIG. 2 is a view in transverse section taken on the line 2-2 of FIG. 1;

FIG. 3 is an enlarged fragmentary view in section taken on the line 3-3of FIG. 2; and

FIG. 4 is a view similar to FIG. 3 but showing a different position ofsome of the parts.

other by insulation 5. For the purpose of reducing the overall height ofthe tank 2, so as to enable the vehicle 1 to negotiate low clearancesfrequently occasioned in rural areas, the tank 2 has an ellipticaltransverse crosssection, the minor axis of which lies in a generallyvertical plane. a

For the purpose of loading the tank 2, a suitable fluid receivingopening, not shown, but of conventional design, is provided beneath theremovable dome-like cover 6. To permit withdrawal of the fluid from thetank 2 an outlet valve, also of conventional design, not shown butenclosed within the housing 7, is provided in the lower end of the tank.To facilitate rapid removal of the collected contents of the tank 2 bypower pumps or the like located at the unloading destination such as acreamery, a breather valve, identified in its entirety by 8, is providedin the upper wall 9 of the tank 2. Breather valve 8 may take anyconventional form such as that shown in Patent No. 2,909,186.

As above indicated, the breather valve 8 is apt to be renderedinoperative under such conditions as freezing of the splashing contentsof the tank 2 during transportation in sub-freezing temperatures. Ifsuch an inoperative breather valve is not detected prior to the powerunloading conditions above described, the upper and lower walls 9, 10 ofthe tank 2 may be caused to collapse so as to render the tank 2 useless.In order to avoid this situation, we provide a tubular valve body 11which projects through the upper wall 9 of the tank 2 with its axis ingeneral alignment with the minor transverse axis of said tank. The lowerend portion of the valve body 11 is formed to define an annular valveseat 12, whereas the opening in the upper end thereof is closed by apuncturable plug identified in its entirety by 13. As shown, the plug 13comprises an annular nut-like member 14 and a replaceable readilyfracturable cap-like insert 15 which may be formed from any suitablematerial, such as plastic. Housed within the tubular valve body 11 is anaxially extended punch 16 formed to define an enlarged poppetvalve-acting head 17 at its lower end. Valve 17 is adapted to havesealing engagement with the valve seat 12 and is yieldingly biasedtoward such engagement by a coil compression spring 18 which isinterposed therebetween and the replaceable insert 15 of the plug 13. Asshown, the insert 15 is formed to define a downwardly opening axialrecess 19 which guides and receives the reduced upper end portion of thepunch 16.

Supported by the bottom wall 10 of the tank 2 is a vertically disposedfinger 20, the upper end 21 of which is normally spaced immediatelyunder and in vertical alignment with the valve-acting head 17 of thepunch 16, as shown particularly in FIG. 3, and is directly engageablewith said head 17 upon relative movement of the walls 9, 10 toward eachother, as shown in FIG. 4. For the purpose of cleansing and sanitation,the finger 20, as well as the depending portions of the valve body 11and head 17, are free of dirt-catching recesses and are also prefer-'ably formed from some non-corrosive material such as stainless steel.

With our novel anti-implosion device immediately above described when,under conditions wherein the breather valve 8 is rendered inoperativeduring rapid toward each other because of the differentials inatmospheric pressure without and within the tank 2. These initialflexing movements, however, will cause the upper end 21 of the finger 20to engage the valve-acting head 17 whereby to unseat same from the seat12, against yielding bias of coil spring 18. Such movement, as indicatedin FIG. 4, will cause the upper end of the punch 16 to fracture thereplaceable insert 15 thereby permitting air to freely enter the tank 2and to equalize the pressures therewithin and without. The walls of thetank 2 are constructed to absorb this amount of distortion withoutdamage and consequently when the air pressure has been equalized withinand without the tank, the upper wall 9 will again assume the position ofFIG. 3 whereby to again space the finger 20 from the valve-acting head17.

Our invention has been thoroughly tested andfound to be completelysatisfactory for the accomplishment of the above objects, and while wehave shown and described a preferred embodiment, we wish it to bespecifically understood that the same is capable of modification withoutdeparture from the spirit and scope of the appended claims.

What is claimed is:

1. In a cross-sectionally elliptical tank for transporting fluids, saidtank being horizontally disposed with its minor transverse axis lying ina generally vertical plane and having a breather valve in its upperportion and a fluid withdrawal valve in its lower portion, theimprovement which comprises (a) a tubular valve body projecting throughthe upper wall of said tank intermediate the ends thereof and with itsaxis in general alignment with said minor axis of said tank,

(b) a readily puncturable plug normally closing the opening defined bysaid tubular body,

(c) and means for puncturing said plug responsive to relative movementof said upper wall toward the lower wall of said tank during fluidwithdrawal under conditions, wherein said breather valve has beenrendered inoperative.

2. The structure defined in claim 1 in which said means includes avertically disposed finger supported by the bottom wall of said tank andhaving its upper end so disposed with respect to said plug tooperatively puncture said plug upon the movement of said tank wallsabove described.

3. The structure defined in claim 2 in which said plug is in the natureof a frangible cap on the upper end of said tubular valve body and inwhich the lower end portion of said body is formed to define an annularvalve seat, and in further combination with an axially extended punchwithin said tubular body, said punch having an enlarged head at itslower end formed to define a valve adapted to have sealing engagementwith said valve seat, and yielding means interposed between said cap andsaid valve-acting head and biasing said head into engagement with saidseat, said finger being adapted to engage said punch and raise sameagainst bias of said yielding means to fracture said cap.

4. The structure defined in claim 3 in which said cap is formed todefine a downwardly opening axial recess which receives and guides theupper end of said punch.

No references cited.

ISADOR WEIL, Primary Examiner

1. IN A CROSS-SECTIONALLY ELLIPTICAL TANK FOR TRANSPORTING FLUIDS, SAIDTANK BEING HORIZONTALLY DISPOSED WITH ITS MINOR TRANSVERSE AXIS LYING INA GENERALLY VERTICAL PLANE AND HAVING A BREATHER VALVE IN ITS UPPERPORTION AND A FLUID WITHDRAWAL VALVE IN ITS LOWER PORTION, THEIMPROVEMENT WHICH COMPRISES (A) A TUBULAR VALVE BODY PROJECTING THROUGHTHE UPPER WALL OF SAID TANK INTERMEDIATE THE ENDS THEREOF AND WITH ITSAXIS IN GENERALY ALIGNMENT WITH SAID MINOR AXIS OF SAID TANK, (B) AREADILY PUNCTURABLE PLUG NORMALLY CLOSING THE OPENING DEFINED BY SAIDTUBULAR BODY,